jenkbuilder: reformatted script end log message
jenkbuilder.pl: check for defined $summary object when starting

- If the $summary object is undefined, the HTTP/HTTPS request to the
  server failed for whatever reason
- Clarified a lot of the POD docs
- Put the sample JSON parameters block into a POD begin/end block
jenkbuilder: Add --debug option, remove "more verbose"
jenkbuilder: Show message for HTTP request errors
jenkbuilder: disable server SSL cert checking